Although these mobile computing devices are very capable in terms of performance and versatility, they are often not as user-friendly as traditional desktop computers. One particular problem area with mobile computing devices is text input. Many applications on mobile computing devices involve text input. Because of the emphasis on mobility, these devices generally do not have a full keyboard for inputting text.
Several keyboardless inputting means are currently available for a mobile computing device. One particular means is the use of a touch screen, which integrates a touch sensitive pad with a display. Generally, a user enters text by writing or tapping on the touch screen using a stylus. A number of different methods may be used by the mobile computing device to enable the user to input text using the touch screen. For example, the mobile computing device may present a virtual keyboard on the touch screen, allowing the user to enter text by tapping on the virtual keyboard. The mobile computing device may also include handwriting recognition software so the user can virtually write the text input on the touch screen. Although the touch screen is capable, it is not very convenient for the user. In particular, the user is required to use two hands and exercise quite a bit of eye-hand coordination. The large size of the costly electronic components and the computing power required also render touch screen technology unfeasible in many applications.
Another keyboardless inputting means that is found on many existing wireless phones is multitap. Multitap uses a conventional number-key pad. Each of the numbers 2 to 9 on a number-key pad is uniquely associated with three to four letters of the alphabet. A user may enter a particular letter by pressing the number key associated with the letter. Since each number key is associated with more than one letter, the user may have to press the number key up to four times to cycle to the desired letter. Once the desired letter is found, the user has to wait until the selection is committed and the letter is inputted. The advantage of multitap is that it allows the user to enter text with one hand. However, multitap requires the user to move his fingers over eight different keys. This wide range of motion demands a great deal of attention by the user, which can be annoying and even dangerous in some situations. Also, multitap is a slow text input method because of the numerous key presses that are required and the wait state associated with each letter input.
An efficient and user-friendly means of inputting text continues to elude those skilled in the art.